1. Field of the Invention
The present invention relates generally to computer drawing applications, and in particular, to a method, apparatus, and article of manufacture for representing a real world component using a single object throughout multiple stages of a drawing.
2. Description of the Related Art
The use of Computer Aided Design (CAD) application programs is well known in the art. CAD application programs are used for generic design or specialized systems such as architecture, engineering, and construction (AEC) systems. For example, a CAD application program may be used in the creation and modification of an HVAC (heating, ventilation, and air conditioning) system, a plumbing and piping system, an electrical system, cable tray, conduit, a communications network, etc.
Such systems may be further broken down into one or more subsystems. A subsystem is any fully connected set of components that share the common function of carrying the same fluid. For example, an HVAC system might include gas pipe, hydronic pipe, and air duct subsystems. Key components link to more than one subsystem and serve the function of transferring energy from one subsystem to the next. For example, cold water might be used to cool air. FIG. 1 illustrates a typical example building system (HVAC) with hydronic piping and air ducting subsystems.
A CAD system may be further utilized to display different systems or subsystems. For example, a CAD program may be used to display a plumbing system model, a fire protection system model, a plumbing riser diagram, a piping system model, sewer piping, an HVAC ductwork model, electrical single-line and multi-line schematics, electrical power and lighting models, electrical cable tray models, etc.
A CAD system is also used at various stages in a building process. FIG. 2 illustrates the AEC design/construction/maintenance process. The CAD program may be used in one or more of the stages indicated (i.e., predesign 200, site analysis 202, schematic/preliminary design 204, design development 206, construction documentation 208, bidding and negotiation 210, construction 212, post-contract/record drawings 214, and/or facilities management 216).
However, at different stages in the design process, different levels of detail may be known (i.e., by the person using the CAD system). For example, during the preliminary design stage 204, a type of equipment may be known but engineering specifications may be incomplete. In another example, specific piping sizes and manufacturer information may be known during the construction stage 212 but not during any stages prior to stage 212.
Based on the differing information known at different stages, different components may be used in a CAD system at each stage. For example, an empty box may be created and used during the predesign stage 200. Once detailed information is known, the empty box is deleted and a new specific component that contains details for the component is added. Thus, in the prior art, different parts are used at different stages in the building development process. While such prior art embodiments may be useful, it is not efficient, and is time consuming during the development process.